Conventionally, in wireless LAN communication such as WiFi™ (Wireless Fidelity), once being connected to an access point, client terminal devices retain an SSID (Service Set Identifier) or the like of the access point. Such a client terminal device is configured, when detecting a known SSID in establishing a subsequent connection, to automatically connect to the access point associated with the known SSID.
The client terminal device also attempts to connect to an access point used for the last connection in a service area including a plurality of access points with which the client terminal has a connection history of the past. FIG. 7 illustrates an operation of a conventional client terminal device when attempting to connect to an access point. A client terminal device 32 automatically attempts to wirelessly connect to an access point 31B used for the last connection even despite the presence of an access point 31A with a higher signal level and a lighter network load.
Patent Literature 1 describes a technology by which base stations each inform a communication terminal about the count of communication terminals that are registered on and managed by the base stations and by which, upon the notification, the communication terminal selects, as a connection destination (for a handover), one of the base stations on which a relatively small count of communication terminals are registered. Patent Literature 2 also describes a wireless LAN system in which an access point, instead of a server, conducts authentication of client terminals.